Stabting mechanism



1,64 2 J. P. JOHNSON I STARTING MECHANISM Filed Sept. 50, 1925 sSheets-Sheet Y l-nv e nto 2,

V 7 1,646,202 1927' J. P. JOHNSON I STARTING MECHANISM- I Filed Sept.50, 1925 3 Sheets-Shaet 3 n'Co 2 Patented Oct. 18, 1927. I 1

JAMES P. JOHNSON, OF CLEVELAND HEIGHTS, OHIO.

STARTING MECHANISM.

Application filed September 30, 1925. Serial No. 59,455.

This invention relates to gearing and more especially to gearing foroperatively connecting a motor-generator with the crank shaft of aninternal combustlon engine which, when running, drives the motorgenerator at a desired speed, the gearing being adapted to provide aspeed-reduction so that the motor-generator, when acting as a mo tor,may rotate the crank shaft for the purpose of starting the engine.

One of the objects of the invention 1s to provide a relatively simplegearing, for the purposes specified, which Wlll be efficient andreliable in operation and which may be manufactured so economically thatit is adapted for commercial production to compete with existing formsof starting mechanism and generator drives.

A further object of the invention is to provide a suitable form ofgearing which will permit the use of a single electrical unit,

in connection with an internal combustion engine, as a generator and asa starting motor.

A further object of the invention is to provide a gearing of the typespecified in which all the working parts are thoroughly housed, for thepurpose of excluding dust and to permit these parts to be efficientlylubricated, and in which the gears are permanently meshed andoperatequietly and without the clashing that is incident to driving gears nowcommonly used.

Other objects of the invention and the features of novelty will beapparent from the following description taken in connection with theaccompanying drawings in which I have illustrated the application of theinvention to a gearing for operatively connecting a motor-generator andthe crank shaft of an internal combustion engine, it being understoodthat this particular application of the invention is merely for thepurpose of illustrating the principles thereof,

: although the invention is applicable for other purposes. In thedrawings, Fig. 1 is an end elevation of a conventional type of internalcombustion engine,

having my invention applied thereto;

Fig. 2 is a longitudinal section through a gearing embodying. mylnvention, the section being on the line 22 of Fig. 1;

Fig. 3 is a section on the line 3 3 of Fig. 1

Fig. 4 is a section on the line 44 of Fig. 2; and

Fig. 5 is a view similar to Fig. 2 but showing another form of theinvention.

Referring to the drawings, 10 indicates the crank shaft of the internalcombustion engine and 11 the usual driving chain that is arranged at thefront end of the engine for the purpose of operatively connecting thecrank shaft with the cam shaft 12 and the auxiliary shaft 13, therebeing a sprocket 14 on the latter, with which the chain 11 meshes. WhileI have illustrated what is known as the chain-drive, in connection withthe engine, it is also customary to dispense with the chain and useintermeshed gears for driving the different shafts and it is, therefore,to be understood that the sprocket 14 may also represent a gear on theauxiliary shaft by means of which the latter is driven.

The chain 11 and the sprockets with which it cooperates are usuallyenclosed in a housing 15 and said housing is provided with a hub 16through which the shaft 13 projects. A motor-generator is indicated at17 and is secured to the side of the engine in any suitable manner (notshown) and has a shaft 18 which is in alignmentwith the shaft 13. Aninternal gear 1.9, preferably having spirally arranged teeth, has atubular extension 20 which is supported in the bearings 21 and 22, inthe hub 16. The outer races of the bearings 21 and 22 are held in properspaced relation by means of the shoulders 23 and 24, respectively, inthe hub 16, and the extension 20 has a shoulder 25 which engages theinner race of the bearing 21 to'hold the gear 19 against axial movementtoward the housing 15. The sleeve 20 is lined with the bearing bushings26 in which the shaft 13 is rotatably mounted. The sprocket 14 is keyedto the shaft 13 and is held against and provided with a. series ofpockets 32 for the hardened steel rollers 33, there being four of theserollers shown in drawin s. The ring 29 has pockets 34 therein, for t erollers 33, these pockets varying in depth,-

as shown in Fi 3, so that theslve town];

be permitted to rotate in the direction of the arrow, i-nFig. 3, butwill be heldagainstrotation in the opposite direction, the constructionbeing a well-known device for accomplishin thisresult. i r The sha t 13has'an enlargement con taining the internal gear 36, which is preferably formed with spiral teeth inclined in. the same direction as theteeth of the gear 19. A disc 37, of friction material, is se- .-'curedto theend of the enlargement 35 by rivets 38, or in any other suitablemanner, and is adapted to engage the face 39 on the inner side of thewall .40 which connects the internal gear 19 with the sleeve 20. Ac'o'verplate .41 is secured to the side of the gear :19 by the bolts 42and has a hub 4-3 that is iprovidel with a bushing 4a in which the shaft1.8 has a hearing. The shaft 18 has a gear or eccentric .45 whichprojects within "the gears 19 and 36 and onwhich there isrotntaihlymounted a pair of gears 46 and 17 which mesh. respectively,with the gears 19 and 36. The gears 46 and a7 are preferably formedintegral so that they will rotate as "a unitary structure, thusconstituting whatis'commonly-known as'za cluster-gear.

A spring disc 4-8 is aerangedbetween the bearing 22 and. the hub of thesprocket 14 and normall tends to move the shaft 13 "toward the right, inFig. 2, so that the disc 37 will beheld in frictional contact with theface 39b t the wallet).

The operation is as follows: YVhen it is desired to start the engine,current is supplied- :to the anotor-generator from a storage ibattery orother source, in the usual inn anner, this causing theshafit 181:0rotate. Since the crank shaft of the engine is stationary, the sprocket1 1 and :shaft1'3 will he held thereby against rotation. It is necessarythat the speed'reduction in the mechanism shall he sufficient to enablea relatively small motorsgenerator to start the engine and, for

practical purposes, aspeed =r-eduction of 13.8

t'o 1 wil=l be satisfactory, this speedreduction being secured by havingthe gears of the; proper toothratios. This speed reductiion' may. beaccomplished by having 26 in the gear 47 and 12-teeth in the gear 36.The gears 19 and 46 will have 4 :8 and 42 teeth, respectively, the teethloeing 0f approximately thesamesize so that thegear 19 will beconsiderably larger than thexg'car The gear 36 being held stationary, bythe engine, the rotation of the shaft 18 will '-'cause the cluster-gearto be carried around by eccentric 45 and rotated thereon by 1 theengagement of the teeth of the gear 47 with those of the gear 36. Thiswill cause the gear :46 to tend to rotate the gear 19in thecounterclockwise, direction, as shown in Fig. 4,, wh1ch,of course,tends-to rotate the sleeve 20 in that direction and carry the rollers 33into the shallow parts of the recesses 34 so asto lock the sleeve 20 tothe 1 stationary 'ring 29. The gear 'l9qwill'be' thereby held againstrotation anc l this will cause the cluster-gear to rotate on the eccentri'c 45 "and effect the rota-tion of the shaft ing to hold the gear 19stationary there is 'suflicient friction in the parts, take n inconnection with the friction betweenwthe'disc j 37 and the wall lfhdueto the end thrust 18 to rotate as "a unit with the shaft 13, therecaused by the spiral teethof the gears, to 3 cause all of the gears, aswell as the shaft thus being .a speed ratio of 1150 1 between.

the shafts 13 and 18. v p y 1 It will be noted from the drawings thatall of the gears are housed within" a chamber formed by th gear. 19, theu ioamlihei cover-plate. 41, thus providing adequate space for lubricantfor the gears and entinely housing them from dust and other foreignsubstances so that the mechanismvisadapted forreli'able and efficientservice and willbe Sub ected to little wear hecause'there is noIGlltlVG-TOtSLtlOIl of the gQEUIPSfiXCGPlZ when the mechanism used forstarting the ngine.

Referring to Fig. 5, it will Joe noted that the construction isessentially the same as that previously described with the exceptionthat the gears 50 and 5.1 and the internal gears '52 and 53have straightspur teeth so that the meshing of these gears does not produce any axialthrusts thereian However, the gear 54, which correspondsto'the sprocket14, has spiral teeth which mesh with a spiral gear 55., the. latter,bein geared to the crankshaft of the engine. n this form of theinventioinsve liavea gear drive between the crankshaft 10 and-theauxiliaryshaft 13., instead ofthe chain drive shown in Fig. 1. The shaft.13 rotates in the direction of the arrow, shown in Fig. 5 and i whenthe mechanism isusedto start the engine and the shaft- 13 is, inthiscase, used as a driving shaft, the .reactionfbetween the gears 54and :55 produces an end thrust in the shaft 13 toward the left which'disengages the friction-disk 37 from the surface 39 and permits thegears 52 and '53 to rotate independently in accordance with thereduction 1n speed effected by the gearing. Under 1 Hill ' ning and themechanism acts as a driver for the motor-generator 17, the torque whichacts on the teeth of the gear 54 is relatively small and insufficient toovercome the tension of the spring 48 so that this spring holds theshaft 13 against movement toward the left and keeps the disk 37 incontact with the surface 39.

It will thus be seen that the modification, shown in Fig. 5, willfunction in substantially the same manner as that shown in F ig. 2 butthe end thrust in the shaft 13 will be produced by the thrust reactionbetween the gears 54 and 55 instead of thethrust reaction between thegears 36 and 47.

Having thus described my invention, I claim:

1. In apparatus of the class described, the combination of a shaftadapted to be operatively connected with the crank shaft of an engine, aspiral internal gear on said shaft, a motor-generator shaft, aneccentric on said motor-generator shaft, a spiral internal gearrotatably mounted with respect to said shafts, a pair of gears rotatableas a unit on said eccentric and meshing, respectively, with saidinternal gears, said internal gears having cooperating friction meansthat are forced into engagement by the end thrust produced by themeshing of said internal gears with said pair of gears, and means forrotation of one of said internal gears in one direction.

2. In apparatus of the class described, the combination of two alignedshafts either of which may drive or be driven by the other, and meansfor operatively connecting said shafts so that one may drive the otherat a different speed or be driven thereby at the same speed comprising apair of coaxial rel. atively rotatable internal gears, one of saidinternal gears being fixed on one of said shafts and the other rotatablewith respect to both of said shafts, a pair of unitary gears which meshrespectively with said internal gears and are rotatably mounted on aneccentric carried by one of said shafts, friction means for operativelyconnecting said internal gears for rotation as a unitwhen one of saidshafts acts as the driver, and means for preventing rotation of saidother internal gear in one direction.

3. In apparatus of the class described. the combination of astationaryhousing, an internal gear having a tubular hub rotatably mounted in saidhousing, means for preventing rotation of said. gear in one directionbut permitting rotation thereof in the opposite direction, ashaftrotatably mounted in said hub and carrying an internal gear, said shaftbeing axially movable, friction for operatively connecting said internalgears to cause them to rotate as aunit when said shaft functions as thedriver for the apparatus, spring means cooperating with said shaft tomove it axially in one direction to make said friction means operativeand yieldable to permit said shaft to move in the opposite direction torender said friction means inoperative, a shaft having an eccentricthereon, and a pair of gears rotatable as a unit on said eccentric andmeshing respectively with said internal gears.

4. In apparatus of the class described, the combination of a stationaryhousing, an internal gear having a tubular hub rotatably mounted in saidhousing means for preventing rotation of said gear in one direction butpermitting rotation thereof in the opposite direction, a shaft rotatablymounted in said hub and carrying an internal gear, said shaft beingaxially movable, friction for operatively connecting said internal gearsto cause them to rotate as a unit when said shaft functions as thedriver for the apparatus, spring means cooperating with said shaft tomove it axially in one direction to make said friction means operativeand yieldable to permit said shaft to move in the opposite direction torender said friction means inoperative. a spiral gear on said shaft theteeth of which are so inclined as to shift said shaft in opposition tosaid spring means to render said friction means inoperative when saidshaft is driven by said apparatus, a shaft having an eccentric thereon,

and a pair of gears rotatable as a unit on said eccentric and meshingrespectively with said internal gears.

In testimony whereof, I hereunto afiix my signature.

JAMES P. JOHNSON.

